1. Field of the Invention
The present invention relates to novel benzo[b]furancarboxamide derivatives, stereo-isomers thereof, process for the preparation of same, and medicine for improving hypermotility of digestive tract, which contains the compound or salt as an effective ingredient.
2. Related Arts
Since 4-amino-5-chloro-N-[(2-diethylamino)ethyl]-2-methoxybenzamide [General name: Metocloplamide ("The Merck Index", 10th Ed. 6063)] had been developed in the 1960s, as an agent for improving hypermotility of digestive tract or anti-vomiting agent, various benzamide derivatives have been synthesized to evaluate pharmacological effect thereof. The main object for developing such derivatives lies in moderating a side effect of Metoclopramide to central system due to its anti-dopamine action, namely extrapyramidal disorder and cryptorrhea (lactation and prolactinemia), and recent years, various reports have been issued on development of derivatives having antagonism to serotonin receptor. A relation between a selective action and structure of these benzamide derivatives has not sufficiently been elucidated, but it has been recognized that a mutual relation between a substituent to amide nitrogen and alkoxy group at 2-position is important [for instance, Jap. Pat. No. Sho 62 (A.D. 1987 )--129279 (A) and "J. Med. Chem.", Vol. 34, page 616 (1991 )]. Under such a technical notion, carboxamide derivatives of benzofuran and benzopyran have been studied, as compounds analogous to the benzamide derivatives [Jap. Pat. Nos. Sho 60 (A.D. 1985--169473(A), Sho 62 (A.D. 1987)--234083(A), Hei 1 (A.D. 1989)--104272(A), Hei 1 (A.D. 1989)--110684(A), Hei 1 (A.D. 1989)--168686, Hei 1 (A.D. 1989)--501226(A) and Hei 4 (A.D. 1992)--295476(A)].